What do the dashboard analytics mean?

Hey everyone, so on my admin portal for my nodebb forum, there are a number of analytics, i.e. things like "page visitors" "page views" etc.

While those are a bit more self explanatory, can someone help me out -- I'm not too sure what the other metrics mean:

Unique visitors

Users

Posts

Topics

Active users, split into "users" and "guests"

All of these have their metric for "day" "week" "month" and "all time" -- it seems that there's no way to check the stats for a certain day in the past, but instead it just calculates the "day" as in "last 24 hours", so it's always changing. If there's a way to extract all these stats and check the stats for a specific day, please let me know!

Anyway so:

For 3+4, my understanding is that a "topic" is a completely new thread while "posts" not only include topics but also comments on each thread, hence the reason the number of "posts" are usually much higher than the number of "topics".

On any given day, the number of users for the last "day" are like 25-30. But whenever I check the dashboard, the active users are always much higher, like 115-150.

Furthermore, there are always a higher number of "guests" (i.e. anonymous users) then "users" (i.e. registered users) in the "active users" section, which is weird because: our forum is only restricted to our customers -- you can't access the community forum unless you actually have an account with us, which would make you a "registered" user.

Okay -- I know this was a lot but any help is appreciated here. To wrap it up:

What constitutes a "guest" and a "user" on nodebb?

Why is the "users" metric per day always much lower than "active users"? How is the "users" metric calculated, if not based off of the "active users" per day?

What's the difference between "unique visitors" and "users"? For reference, the "unique visitors" per day count we have is usually around 280-300, while once again, our "users" count is usually 25-30.

To confirm: a "topic" is a completely new thread while "posts" include not only entirely new threads but also comments on new/old threads, right?

Thank you in advance to anyone that can help with any of these. Cheers!

Those show the unique ips that visit the forum. I recently changed the calculation for all time to it doesn't count all the ips. Thats why all time shows less than month.
You can reset it by doing.
redis-cli
del ip:recent
or if you are using mongodb
mongo
db.objects.remove({"_key":"ip:recent"});